1. Field of the Invention
This invention relates to piperazine derivatives, vasodilators containing the same and a vasodilating method for vascular disorders. The piperazine derivatives provided by the present invention are novel compounds which have potent vasodilating activities. Therefore, they are useful for the therapy of vascular disorders such as cerebral, coronary and peripheral vascular diseases, which are to be treated by increasing blood flow.
2. Description of the Prior Art
Vascular diseases occuring after cerebral embolism, myocardial infarction or the like have recently taken a large portion of adult diseases, and development of drugs effectively preventing such disorders is highly desirable.
There have been developed a large number of vasodilators including derivatives of 3,4,5-trimethoxycinnamic acid such as, for example, 1-[3-(3,4,5-trimethoxyphenyl)-2-propenoyl]-piperazine (cinepazide), which are not necessarily satisfactory in efficacy of the drug.